Major study delivers positive news for Kiwi prostate cancer patients

Results from a major international prostate cancer study have found men with early disease who undergo a highly-targeted type of radiotherapy not only finish treatment more quickly but reduce the risk of two major, long-term side effects.

The newly-published PACE-A study, carried out in 12 leading UK cancer centres, found men with early-stage disease who were treated with a five-dose course of Stereotactic Body Radiation Therapy (SBRT) experienced notably less downstream problems from the two side effects which concern many the most - urine incontinence and sexual dysfunction - compared to men who underwent a prostatectomy –surgical removal of the prostate gland.

SBRT is available in several cancer centres nationwide. It is delivered by either a linear accelerator machine or by a robotic radiotherapy unit. It delivers highly targeted treatment, minimising damage to surrounding healthy tissue.

With 4000 men diagnosed with prostate cancer in this country every year, Radiation Oncologists here say these landmark results should help inform Kiwi men and their doctors when making treatment decisions.

“As a clinician, being able to sit down with a patient and tell him that SBRT will highly likely eradicate his disease effectively in five treatments and also reduce his chances of incontinence and impotence, is extremely positive,” Auckland Radiation Oncologist, Associate Professor Sasso says.

“It’s very important that men diagnosed with early-stage, localised disease are informed about the option of SBRT, to see if it might be suitable for them.”

Both a 2021 New Zealand Ministry of Health directive, and a position statement from the Royal Australia and New Zealand College of Radiologists (RANZCR) highlight the importance of prostate cancer patients being referred to a urologist as well as a radiation oncologist, to ensure they are able to make well-informed decisions about their treatment options.

Auckland Radiation Oncology (ARO), Auckland City and Starship Hospital radiation oncologist Dr Ramesh Pandey believes treatment should be a shared decision-making process.

“SBRT may be the best option for some men while surgery may still suit others, but men certainly need to explore all their options,” Dr Pandey says.

For decades New Zealand men have been offered both prostatectomy and conventional radiation therapy to treat early-stage prostate cancer – sometimes both – requiring up to 20 treatments over a 4-week course.

However, the very latest and most advanced type of SRBT is now available in New Zealand – which reduces treatment time down to just 5 visits.

Called CyberKnife, it’s a lightweight, fully mobile robotic device. Tiny gold/titanium markers inserted inside the prostate gland enable the CyberKnife robot to continually track the prostate during treatment, adjusting the delivery of radiation beams to accurately target the cancer from hundreds of different directions.

“CyberKnife delivers cutting-edge treatment with sub-millimetre precision,” Associate Professor Sasso says.

“One problem we’ve always experienced radiating the prostate is the fact the prostate gland isn’t set in concrete - it moves when a patient breathes”, says Dr Pandey.

He says CyberKnife solves this problem, detecting the patient’s slightest movement via the fiducials, adjusting the beams to immediately re-direct treatment where needed reducing radiation dosage to the surrounding organs.

“This improves radiotherapy precision, allowing us to deliver an effective dose and simultaneously spare both the bladder and bowel irradiation, reducing side effects significantly,” Dr Pandey says.

CyberKnife is available privately at Auckland Radiation Oncology (ARO), and for patients whose insurance policies include cover for radiation therapy.

Associate Professor Sasso says preliminary results from a second trial, PACE-B – show SBRT also delivers a five-year prostate disease control rate of 95.8 per cent compared to 94.6 per cent with conventional radiotherapy.

The Prostate Cancer Foundation says the much-awaited PACE-A results give it a “great cause for enthusiasm” about SBRT’s overall effectiveness as a treatment, and its side-effect profile.

“We are pleased that ARO along with other providers are working hard to make this treatment modality available to patients around New Zealand,” Chief Executive Peter Dickens says.

“We would urge all those affected by a prostate cancer diagnosis to explore all of the treatment options open to them so that they, in conjunction with their healthcare teams, can ensure they choose the treatment that will result in the best outcomes for them.”